Precise maxillofacial soft tissue reconstruction: A combination of cone beam computed tomography and 3dMD photogrammetry system.

Introduction: The reconstruction of both extra- and intra-oral soft tissue defects, particularly in restoring the morphology of the lip and the corners of the mouth, has posed a significant challenge for surgeons. Inappropriate methods often lead to maxillofacial deformity which then causes psychological and functional problems. This study aimed to address the challenge of reconstructing extensive and complex maxillofacial soft tissue defects, mainly focusing on the lip, the corners of the mouth, and the surrounding areas. Materials and methods: We developed a reconstruction approach by combining the 3dMDface System (3dMD) with the cone beam computed tomography (CBCT). Firstly, with the extra-oral incision line, we evaluated the shape and the size of the extra-oral defect with 3dMD digitally. Then we used the corresponding maxillary and mandible tooth positions to record the intra-oral defect, which was then converted to digital images by combining 3dMD and CBCT. The islands of the anterolateral thigh perforator flap were then designed after the locations of the perforators were detected with Doppler ultrasonography. Results: A clinical case diagnosed as dermatofibrosarcoma protuberans was presented to illustrate the approach. The patient's tumor resection and the size of multiple defects were measured and simulated via the virtual surgery system. A three-island perforator flap from the descending branch of the lateral femoral circumflex artery was designed accurately. Two weeks postoperatively, the flap was healed as anticipated and the patient was satisfied with the profile. Conclusion: The combination of the 3dMD and CBCT technologies improves the accuracy and fitness of extra- and intra-oral soft tissue reconstruction.

The oligodontia phenotype in a X-linked hypohidrotic ectodermal dysplasia patient with a novel EVC2 variant.

Objectives: To analyse the pathogenic genes in a patient with hypohidrotic ectodermal dysplasia (HED) and explore the relationship between pathogenic genes and the oligodontia phenotype. Methods: Clinical data and peripheral blood were collected from a patient with HED. Pathogenic genes were analysed by whole-exon sequencing (WES) and verified by Singer sequencing. The secondary and tertiary structures of the variant proteins were predicted to analyse their toxicity. Results: The patient exhibited a severe oligodontia phenotype, wherein only two deciduous canines were left in the upper jaw. WES revealed a hemizygous EDA variant c.466C > T p.(Arg156Cys) and a novel heterozygous EVC2 variant c.1772T > C p.(Leu591Ser). Prediction of the secondary and tertiary structures of the EDA variant p.(Arg156Cys) and EVC2 variant p.(Leu591Ser) indicated impaired function of both molecules. Conclusion: The patient demonstrated a more severe oligodontia phenotype when compared with the other patients caused by the EDA variant c.466C > T. Since Evc2 is a positive regulator of the Sonic Hedgehog (Shh) signal pathway, we speculated that the EVC2 variant p.(Leu591Ser) may play a synergistic role in the oligodontia phenotype of HED, thereby exacerbating the oligodontia phenotype. Knowledge of oligodontia caused by multiple gene variants is of great significance for understanding individual differences in oligodontia phenotypes.

Compound heterozygous WNT10A missense variations exacerbated the tooth agenesis caused by hypohidrotic ectodermal dysplasia.

BACKGROUND: The aim of this study was to analyse the differences in the phenotypes of missing teeth between a pair of brothers with hypohidrotic ectodermal dysplasia (HED) and to investigate the underlying mechanism by comparing the mutated gene loci between the brothers with whole-exome sequencing. METHODS: The clinical data of the patients and their mother were collected, and genomic DNA was extracted from peripheral blood samples. By Whole-exome sequencing filtered for a minor allele frequency (MAF) ≤0.05 non-synonymous single-nucleotide variations and insertions/deletions variations in genes previously associated with tooth agenesis, and variations considered as potentially pathogenic were assessed by SIFT, Polyphen-2, CADD and ACMG. Sanger sequencing was performed to detect gene variations. The secondary and tertiary structures of the mutated proteins were predicted by PsiPred 4.0 and AlphaFold 2. RESULTS: Both brothers were clinically diagnosed with HED, but the younger brother had more teeth than the elder brother. An EDA variation (c.878 T > G) was identified in both brothers. Additionally, compound heterozygous variations of WNT10A (c.511C > T and c.637G > A) were identified in the elder brother. Digenic variations in EDA (c.878 T > G) and WNT10A (c.511C > T and c.637G > A) in the same patient have not been reported previously. The secondary structure of the variant WNT10A protein showed changes in the number and position of α-helices and ß-folds compared to the wild-type protein. The tertiary structure of the WNT10A variant and molecular simulation docking showed that the site and direction where WNT10A binds to FZD5 was changed. CONCLUSIONS: Compound heterozygous WNT10A missense variations may exacerbate the number of missing teeth in HED caused by EDA variation.

AKT from dental epithelium to papilla promotes odontoblast differentiation.

Epithelial-mesenchymal interactions occur during tooth development. The dental epithelium (DE) is regarded as the signal center that regulates tooth morphology. However, the mechanism by which DE regulates the differentiation of mesenchyme-derived dental papilla (DP) into odontoblasts remains unclear. Using miniature pigs as a model, we analyzed the expression profiles of the DE and DP during odontoblast differentiation using high-throughput RNA sequencing. The phosphatidylinositol-3-kinase (PI3K)/AKT pathway is one of the most enriched pathways in both DE and DP. The PI3K/AKT pathway was first activated in the inner enamel epithelium but not in the DP on embryonic day 50. This pathway was then activated in the odontoblast layer on embryonic day 60. We showed that AKT activation promoted odontoblast differentiation of DP cells. We further demonstrated that activation of PI3K/AKT signaling in the DE effectively increased the expression levels of AKT and dentin sialophosphoprotein in DP cells. Additionally, we found that DE cells secreted collagen type IV alpha 6 chain (COL4A6) downstream of epithelial AKT signaling to positively regulate mesenchymal AKT levels. Therefore, our data suggest that PI3K/AKT signaling from the DE to the DP promotes odontoblast differentiation via COL4A6 secretion.

Novel acoustic radiation force optical coherence elastography based on ultrasmall ultrasound transducer for biomechanics evaluation of in vivo cornea.

We developed a novel acoustic radiation force optical coherence elastography (ARF-OCE) based on an ultrasmall ultrasound transducer for quantitative biomechanics evaluations of in vivo cornea. A custom single-sided meta-ultrasonic transducer with an outer diameter of 1.8 mm, focal spot diameter of 1.6 mm, central frequency of 930 kHz, and focal length of 0.8 mm was applied to excite the sample. The sample arm of the ARF-OCE system employed a three-dimensional printed holder that allowed for ultrasound excitation and ARF-OCE detection. The phase-resolved algorithm was combined with a Lamb wave model to depth-resolved evaluate corneal biomechanics after keratoconus and cross-linking treatments (CXL). The results showed that, compare to the healthy cornea, the Lamb wave velocity was significantly reduced in the keratoconus, increased in the cornea after CXL, and increased with cross-linked irradiation energy in the cornea. These results indicated the good clinical translation potential of the proposed novel ARF-OCE.

In Vivo Evaluation of the Effects of SMILE with Different Amounts of Stromal Ablation on Corneal Biomechanics by Optical Coherence Elastography.

This work aims to depth-resolved quantitatively analyze the effect of different stromal ablation amounts on the corneal biomechanical properties during small incision lenticule extraction (SMILE) using optical coherence elastography (OCE). A 4.5-MHz ultrasonic transducer was used to excite elastic waves in the corneal tissue. The OCE system combined with the antisymmetric Lamb wave model was employed to achieve a high-resolution, high-sensitivity, and depth-resolved quantitative detection of the corneal Young's modulus. Eighteen rabbits were randomly divided into three groups; each group had six rabbits. The first and second groups underwent -3D and -6D SMILE surgeries, and the third group was the control group, respectively. Young's modulus of the corneal cap and residual stromal bed (RSB) were both increased after SMILE, which shared the stress under intraocular pressure (IOP). Furthermore, the Young's modulus of both the corneal cap and RSB after 3D SMILE group were significantly lower than that in the -6D group, which indicated that the increases in the post-operative corneal Young's modulus were positively correlated with the amount of stromal ablation. The OCE system for quantitative spatial characterization of corneal biomechanical properties can provide useful information on the extent of safe ablation for SMILE procedures.

NIR-Activated Multimodal Photothermal/Chemodynamic/Magnetic Resonance Imaging Nanoplatform for Anticancer Therapy by Fe(II) Ions Doped MXenes (Fe-Ti3 C2 ).

2D MXene, Ti3 C2 (TC), has displayed enormous potential in applications in photothermal therapy (PTT), attributing to its biocompatibility and outstanding photothermal conversion capability. However, some tumor ablations are difficult to be realized completely by monotherapy due to the essential defects of monotherapy and intricate tumor microenvironment (TME). In this work, the appropriate doped Fe2+ ions are anchored into the layers of 2D ultrathin TC nanosheets (TC NSs) to synthesize a novel multifunctional nanoshell of Fe(II)-Ti3 C2 (FTC) through interlayer electrostatic adsorption. FTC possesses superior photothermal conversion efficiency (PTCE) than TC NSs, attributing to the enhanced conductivity promoted by interlaminar ferrous ion-channels. Moreover, Fenton reaction based on ferrous ions endows FTC the abilities of reactive oxide species (ROS) releasing and glutathione (GSH) suppression triggered by near-infrared (NIR) laser, featuring splendid biocompatibility and curative effect in hypoxic TME. Meanwhile, magnetic resonance imaging (MRI) responding in FTC reveals the potential as an integrated diagnosis and treatment nanoplatform. FTC could provide new insights into the development of multimoded synergistic nanoplatform for biological applications, especially breaking the shackles of MXenes merely used as a photo-thermal agent (PTA), adopting it to bioimaging sensor and drug loading.

Leptin regulates OPG and RANKL expression in Gingival Fibroblasts and Tissues of Chronic Periodontitis Patients.

Objective: Chronic periodontitis is a bone-destructive disease affecting periodontal support structures. Although leptin has a protective effect against periodontitis, the underlying mechanism remains unclear. Therefore, this study aimed to investigate the possible role of leptin by examining its relationship with OPG and RANKL in human gingival tissues obtained from patients with chronic periodontitis. Method: Twenty-two patients with chronic periodontitis were enrolled (10 with moderate periodontitis and 12 with severe periodontitis) in the experimental group, and 12 healthy individuals were enrolled in the control group. Gingival tissue samples were collected, and the protein levels and localization of leptin, OPG, and RANKL were studied using immunohistochemistry (IHC). The staining intensities of leptin, OPG, and RANKL were correlated with the periodontal clinical index. Moreover, real-time quantitative PCR (RT-qPCR) was used to determine OPG and RANKL mRNA levels in gingival fibroblasts stimulated with gradient concentrations of leptin protein in vitro. Result: Leptin, OPG, and RANKL were located in the cytoplasm of gingival epithelial cells and the connective tissue. Leptin was widely and significantly expressed in the control group, whereas it was lightly stained in the severe group. RANKL was lightly stained in the control group, whereas it was widely and significantly expressed in the severe group. The control and the moderate groups had similar OPG levels, which were significantly higher than that in the severe group. Leptin was positively correlated with OPG(r = 0.905, p < 0.01) and negatively correlated with RANKL (r = -0.635, p < 0.01). In vitro low concentrations of leptin led to an increased OPG/RANKL mRNA ratio, whereas the opposite effect was observed at high concentrations. Conclusion: Leptin can regulate OPG and RANKL expression in gingival fibroblasts and may thus play a role in the development of chronic periodontitis by modulating the OPG/RANKL ratio.

Oral submucous fibrosis transforming into squamous cell carcinoma: a prospective study over 31 years in mainland China.

OBJECTIVE: Oral submucous fibrosis (OSF) is an oral mucous disease caused by betel quid chewing. It is controversial whether OSF can transform into oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: In this prospective study, a group of 567 patients with OSF were enrolled from 1986 to 2017 and followed-up until 2019. The cancerous information was collected and analyzed. RESULTS: OSF transformed into OSCC in 32 cases (32/567, 5.6%). The patient's age ranged from 20 to 69 years, and the average age was 52 years. The time taken for transformation ranged from 2 to 24 years, the average being 8.6 years. The cancerous transformation occurred in 18 patients (56%) from years 2 to 9, in 13 patients (41%) from years 10-19 and in 1 patient (3%) from 24 years. We analyzed the betel quid chewing habits and found all 32 patients with OSCC-chewed betel quid. Betel quid chewing was most prevalent in patients aged 40-69 years. Sixteen patients had chewed betel quid for 10-19 years (16/32, 50%) and 19 patients (60%) chewed 10-19 slices each day. The OSCC was located in the left or right buccal regions in 23 patients (23/32; 72%) and in the left or right lingual regions in 4 patients (4/32; 12%). Well, moderately and poorly differentiated squamous cell carcinoma was present in 23 patients (23/32; 72%), 4 patients (3/32; 9%), and 5 patients (5/32; 16%), respectively. CONCLUSION: Our findings supported that OSF is a real oral premalignant disorder. CLINICAL RELEVANCE: The long duration of the transformation from the OSF to OSCC suggests more frequent examinations and corresponding treatments are necessary for OSF patients.

Strategy for Correction of the Whistling Deformity in Secondary Cleft Lip Reconstruction.

BACKGROUND: Following primary repair of a cleft lip, patients present with many facial deformities. One of the commonly observed sequelae of cleft lip repair is a whistling deformity. This retrospective study was carried out to evaluate the outcomes following correction of whistling deformities in secondary cleft lip reconstruction. METHODS: We retrospectively reviewed the hospital records of patients with various whistling deformities who underwent repair from April 1989 to March 2018; 2 surgeons performed the repair using either the double movable mucomuscular complex flaps technique, modified Abbe flap technique, or Abbe flap technique. The postoperative anatomical structure and aesthetic effects of the surgery were evaluated. RESULTS: In total, 136 patients were included in this study. Among these patients, 60 (44.2%) had a grade I whistling deformity and 47 (34.5%) had a grade II deformity and repair was performed using the double movable mucomuscular complex flaps technique and modified Abbe flap transfer technique, respectively, whereas the Abbe flap transfer technique was used in 16 patients (11.8%) and 13 patients (9.5%) with a grade III and grade IV whistling deformity, respectively. All patients were found to have normal postoperative anatomical structures and aesthetic effects of the upper lip, with all patients experiencing mild to moderate postoperative edema of the upper lip, and 29 cases (21.3%) developed an inconspicuous scar. CONCLUSION: The repair technique should be chosen based on the type of whistling deformity.

Application of a chimeric ALT perforator flap with vastus lateralis muscle mass in the reconstruction of the defects after radical resection of a buccal carcinoma: A retrospective clinical study.

BACKGROUND AND OBJECTIVES: Aggressive resection of buccal cancer simultaneously leaves both oral and lateral facial defects. It is unknown whether a perforator-based chimeric anterolateral thigh (ALT) flap, with a muscular component, is suitable for the reconstruction of these complicated defects. METHODS: In this retrospective study, 48 patients with a buccal carcinoma (T2 N0-1 M0), who underwent extensive surgical resection, were enrolled. Twenty-seven cases underwent reconstruction using the classical ALT perforator flap (classical group), and 21 cases used the chimeric ALT perforator flap with vastus lateralis muscle mass (chimeric group). The incidence of wound infection, lower limb extremity function, facial appearance, survival curves, and quality of life were compared between groups. RESULTS: The incidence of wound infection or effusion was lower in the chimeric group than in the classical group. The aesthetic result achieved in the chimeric group was better than in the classical group. Meanwhile, there was no significant difference in the function of the donor site between groups. CONCLUSIONS: The chimeric ALT perforator flap, with a muscular component, can reconstruct both the oral and lateral face defects accurately. It sustains the profile of the lateral face and decreases the incidence of wound infection.

Expression and methylation of Dickkopf-1 in the pathogenesis and malignant transformation of oral submucous fibrosis.

BACKGROUND: Dickkopf-1 is an inhibitor of the Wnt/ß-catenin pathway, but the role of Dickkopf-1 in oral submucous fibrosis remains unclear. We evaluated the protein expression and gene methylation levels of dickkopf-1 to determine the mechanism underlying abnormal Wnt/ß-catenin pathway activation. METHODS: Healthy mucosa, oral submucous fibrosis, oral squamous cell carcinoma, and cancer-adjacent tissues were collected. The expression and promoter methylation levels of dickkopf-1 were analyzed. RESULTS: The expression levels of dickkopf-1 in oral submucous fibrosis and oral squamous cell carcinoma tissues were lower than those in healthy and cancer-adjacent tissues. The methylation levels of the dickkopf-1 gene in oral submucous fibrosis and oral squamous cell carcinoma tissues were higher than those in healthy and cancer-adjacent tissues. Dickkopf-1 expression was negatively correlated with dickkopf-1 gene methylation. CONCLUSIONS: High dickkopf-1 methylation levels in oral submucous fibrosis and oral squamous cell carcinoma tissues may decrease dickkopf-1 expression, which may induce an abnormal activation of the Wnt/ß-catenin pathway and oral submucous fibrosis pathogenesis.

Application of chimerical ALT perforator flap with vastus lateralis muscle mass for the reconstruction of oral and submandibular defects after radical resection of tongue carcinoma: a retrospective cohort study.

BACKGROUND: Patients with tongue carcinoma who undergo combined tongue and neck radical resection often have simultaneous oral and submandibular defects. Due to its high flexibility, the anterolateral thigh (ALT) perforator flap is gradually being adopted by surgeons for oral reconstruction. However, the tissue volume of perforator flaps is insufficient for the reconstruction of both the oral and submandibular regions. In this retrospective cohort study, we compared the postoperative outcomes and complications between patients reconstructed with using the classical ALT perforator flap and patients reconstructed using the chimeric ALT perforator flap with vastus lateralis muscle mass. METHODS: From August 2017 to August 2019, 25 patients underwent reconstructive therapy using a classical ALT perforator flap (classical group), while 26 patients were reconstructed with the chimeric ALT perforator flap (chimeric group) after radical resection of tongue cancer in Xiangya Hospital, Central South University. The flap survival rate, incidence of submandibular infection, lateral appearance, lower extremity function, and quality of life were compared between the two groups. RESULTS: There were no differences in flap survival rate and postoperative lower extremity function between the two groups. The incidence of submandibular infection was 15.4 and 40% in the chimeric and classical group, respectively. The duration of recovery was 12.20 ± 2.69 and 15.67 ± 4.09 days in the chimeric and classical group, respectively. The submandibular region fullness was satisfactory in the chimeric group. The postoperative quality of life in the chimeric group was better than that in the classical group (P < 0.05). CONCLUSIONS: The chimerical ALT perforator flap with muscle mass reconstructs both the oral and submandibular defects accurately. It maintains the profile and fullness of the submandibular region and may reduce the incidence of submandibular infection.

Analysis of risk factors for multiple primary oral squamous cell carcinoma: a cohort study.

OBJECTIVE: Chewing betel quid (CBQ) is popular in Southeast Asia, resulting in a high incidence of oral squamous cell carcinoma (OSCC). The incidence of multiple primary oral cancer (MPOC) has gradually increased and has become one of the main causes of OSCC treatment failure. However, it is unclear whether the high incidence of MPOC is also correlated with the habit of CBQ. MATERIALS AND METHODS: In this retrospective study, 915 OSCC patients were enrolled. MPOC incidence and characteristics were analyzed. CBQ and other risk factors for MPOC were investigated by chi-squared test and logistic stepwise regression analysis. RESULTS: Among 915 patients, 15 were diagnosed with synchronous MPOC. After follow-up, 60 of 915 patients developed a second or third primary lesion site and were diagnosed with metachronous MPOC. The remaining 840 patients were then diagnosed with single primary oral cancer (SPOC). The cumulative incidence of MPOC in all OSCC patients was 8.2%. CBQ and the related oral submucous fibrosis (OSF) were found to be independent risk factors of MPOC (P < 0.001). Both MPOC and SPOC patients with a CBQ habit were much younger than those who did not have a CBQ habit (P < 0.001). The buccal mucosa was the most common primary occurrence site (35.9%) in MPOC cases, and almost all MPOC patients with buccal cancer had previously suffered from OSF (88.9%). CONCLUSION: CBQ and CBQ-related OSF, for the first time, are identified as the independent risk factors of MPOC. Prevention and treatment of OSF as well as cessation of CBQ are expected to become new approaches to reduce the incidence of MPOC. CLINICAL RELEVANCE: More frequent physical examinations should be undertaken in OSCC patients with CBQ or CBQ-related OSF.

Biomechanical stress regulates mammalian tooth replacement via the integrin ß1-RUNX2-Wnt pathway.

Renewal of integumentary organs occurs cyclically throughout an organism's lifetime, but the mechanism that initiates each cycle remains largely unknown. In a miniature pig model of tooth development that resembles tooth development in humans, the permanent tooth did not begin transitioning from the resting to the initiation stage until the deciduous tooth began to erupt. This eruption released the accumulated mechanical stress inside the mandible. Mechanical stress prevented permanent tooth development by regulating expression and activity of the integrin ß1-ERK1-RUNX2 axis in the surrounding mesenchyme. We observed similar molecular expression patterns in human tooth germs. Importantly, the release of biomechanical stress induced downregulation of RUNX2-wingless/integrated (Wnt) signaling in the mesenchyme between the deciduous and permanent tooth and upregulation of Wnt signaling in the epithelium of the permanent tooth, triggering initiation of its development. Consequently, our findings identified biomechanical stress-associated Wnt modulation as a critical initiator of organ renewal, possibly shedding light on the mechanisms of integumentary organ regeneration.

Retracted Article: Knockdown of long non-coding RNA OIP5-AS1 suppresses cell proliferation and migration in ox-LDL-induced human vascular smooth muscle cells (hVMSCs) through targeting miR-152-3p/PAPPA axis.

Emerging evidence has demonstrated that long non-coding RNA Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) is associated with cellular behaviors among malignant tumors. However, the role of OIP5-AS1 in atherosclerosis remains largely undefined. The aim of this study was to explore the expression and role of OIP5-AS1 in a cell model of atherosclerosis, as well as the underlying mechanism. We found that expression of OIP5-AS1 was upregulated in human vascular smooth muscle cells (hVMSCs) under oxidized low density lipoprotein (ox-LDL) administration, and knockdown of OIP5-AS1 suppressed cell viability (CCK-8) and proliferating cell nuclear antigen (PCNA) protein level in ox-LDL-treated hVMSCs, as well as inhibited cell migration rate (wound healing assay) and protein expression of matrix metalloproteinase (MMP)-2 and MMP-9. Mechanically, OIP5-AS1 functioned as competing endogenous RNA (ceRNA) to positively regulate PAPPA expression through sponging miRNA-152-3p (miR-152), and pregnancy-associated plasma protein A (PAPPA) was identified as a downstream target gene for miR-152. Moreover, expression of miR-152 was downregulated and PAPPA was upregulated in ox-LDL-treated hVMSCs. Similarly to OIP5-AS1 knockdown, miR-215 overexpression could inhibit cell proliferation and migration of hVMSCs administrated by ox-LDL, which was abated by PAPPA upregulation. Moreover, miR-215 downregulation partially reversed the suppressive role of OIP5-AS1 knockdown as well. In conclusion, knockdown of OIP5-AS1 suppressed ox-LDL-treated hVMSC proliferation and migration presumably through targeting miR-152/PAPPA axis, suggesting a novel OIP5-AS1/miR-152/PAPPA pathway in atherogenesis.

[Evaluation of continuous curvilinear buccal-cervical incision in combined radical resection of buccal cancer].

PURPOSE: To evaluate the clinical effect of continuous curvilinear buccal-cervical incision in combined radical resection of buccal cancer. METHODS: From January 2015 to December 2018, a total of 87 patients with buccal cancer were collected, of whom 42 underwent continuous curvilinear buccal-cervical incision (experimental group) and 45 underwent conventional cervical T shaped incision combined with a buccal incision (control group). Exposure of surgical filed in two groups was evaluated. The length of incision, duration of radical resection, and the incidence of postoperative complications were compared between two groups. The patients were followed-up for 7-43 months. Modified vancouver scar scale (VSS) and University of Washington Quality of Life (UW-QOL) were used to evaluate the postoperative scar and quality of life in both groups. Statistical analysis was performed on the data using SPSS 22.0 software package. RESULTS: The length of the incision in the experimental group was (36.40±5.08) cm, which was shorter than that of the control group (39.93±5.22) cm. Duration of combined radical resection in the experimental group was shorter than that of the control group. The incidence of neck complications in the experimental group was lower than that of the control group. The postoperative scar assessment and quality of life of the experimental group were better than that of the control group. The difference was statistically significant (P<0.05). There was no significant difference between the two groups in terms of the exposure of the surgical field, postoperative recurrence and metastasis rate. CONCLUSIONS: Continuous curvilinear buccal-cervical incision has good exposure of the surgical field and shorter duration of radical resection, which ensures en bloc resection of tumor and cervical lymph nodes. It limits the formation of skin cicatrix, reduces the occurrence of postoperative complications and results in a good aesthetic and functional effect, therefore it is a recommended incision for clinical practice.

[The influence of different modes of delivering postoperative instructions on the side effects of wisdom tooth extraction].

PURPOSE: To study the difference between the distinct ways of delivering postoperative instructions to reduce the side effects of wisdom tooth extraction, including pain, bleeding and swelling, and improve the degree of satisfaction of the patients. METHODS: A group of 150 patients who underwent wisdom tooth extraction in the Department of Oral and Maxillofacial Surgery of Xiangya Hospital, Central South University between Jan. 2018 to Oct. 2018 were selected in this research randomly. They were divided into 3 groups randomly and 50 patients in each group. Patients in group 1 received verbal postoperative instructions, patients in group 2 received written postoperative instructions, and patients in group 3 received verbal plus written postoperative instructions. The information of age, sex and education level was collected for each patient. The side effects of pain, bleeding and swelling, and the satisfactory degree of the patients were recorded 7 days after surgery. SPSS 22.0 software package was used for statistical analysis. RESULTS: There were 81 women and 69 men among 150 patients. The mean age was 24.6±2.6 years. The results showed that the degree of pain of group 1 was significantly higher than group 2 (P=0.001) and group 3 (P=0.000). The satisfactory degree of group 1 was the lowest, and group 3 was the highest. CONCLUSIONS: The way of delivering postoperative instructions affects pain and satisfactory degree after wisdom tooth extraction.